Heat exchange apparatus



Feb. 5, 1935. C. ROBlNSON 1,989,772

HEAT EXCHANGE APPARATUS Filed Dec. 30, 1955 llllllll @1 WML PatentedFeb. 5, 1935 UNITED STATES HEAT EXCHANGE APPARATUS Charles Robinson,Trent Works, Burton-on-Trent, England Application December 30, 1933,Serial No. 704,688 In Germany December 15, 1933 1 Claim.

This invention relates to heat exchange apparatus of the type comprisinga hollow body including a number of substantially horizontally arrangedtubes attached to hollow headers at the ends, one of the liquidscirculating in these tubes and headers, the apparatus also including adistributor (not shown) at the top to which the other liquid is suppliedand from which it flows down over the exterior surface of thesubstantially horizontally arranged tubes.

In this type of apparatus it is known toI construct the body tubes ofroughly triangular section, the bases of the triangles being placedvertically, and the apex of each triangle, which is usually rounded,being directed outwardly, and the tubes thus arranged being solderedtogether back to back. It is known also to construct the tubes of beadedform, i. e. at each termination of a base portion of the tube, a bead oroutwardly projecting hollow part is formed, and in constructing thebodies of such heat exchangers, it has been proposed to place such tubesback to back, i. e. with the bases towards each other and in staggeredrelationship, the bases of the tubes on opposite sides of the body beingunited by solder, and the beaded edges of adjacent tubes on the sameside being spaced apart and also united by solder.

In such an arrangement it was essential to space the tubes on the sameside of the body apart somewhat and to unite such tubes together by aconsiderable body of solder disposed between adjacent beaded edges. Ifthis had not been done, when a single tube was removed from thestructure for repairs or replacement, then the whole structure would besevered into two parts.

The object of providing the tubes with beaded edges was to reduce theproportion of the cooling surface formed by solder, it being recognizedthat such solder is liable to chemical action by the detergents used inwashing the apparatus, with the result that any solder which comes intocontact with the detergent has its surface roughened and pitted andbecomes a resting place for undesirable bacteria.

Thus in the bodies of heat exchangers of the kind referred to, as atpresent constructed, a considerable amount of solder was employed at thebase of the tubes, and the object of the present invention is to reduceto an absolute minimum the amount of such solder and conversely toensure that practically the whole of the surface over which the liquidtravels is cooling surface.

According to the present invention, in a body for a heat exchangeapparatus of the kind referred to, I provide the combination of acentral partition plate, to opposite sides of which are soldered tubesof beaded section, whereby the external surface over which one of theliquids flows is practically free from solder.

With such an arrangement if it becomes necessary to remove a tube forrepairs or replacement, the structure is not severed into two parts bysuch removal, as the remaining tubes are all united together by thecommon partition to which they are soldered.

Referring to the drawing:-

Figure 1 is a view in side elevation.

Figure 2 is a sectional view on line 2-2 of Figure 1.

Figure 3 is a similar View to Figure 2, but illustrating a modification.

In the construction illustrated, the body of the heat exchangercomprises a structure incorporating horizontally arranged tubes 3connected to tubular headers 4 at the ends, one of the liquids undertreatment circulating in these tubes or headers.

Instead of securing the tubes 3 directly to each other back to back, Iprovide a central partition 5, and the tubes 3 are supported solely bybeing soldered to this partition.

Each tube is of somewhat triangular form having converging sides 6, arounded apex '7, a base 8, at the terminations of which are roundedbeads 9.

The rounded bears 9 of adjacent tubes are placed as closely together aspossible, leaving only sufficient space for the solder to pass betweenthe tubes to the partition plate, so that the width of the line ofsolder exposed between the beads of the tubes is reduced to an absoluteminimum.

In the construction shown in Figure 3, the tubes 3 instead of beingmounted in staggered relationship on either side of the centralpartition are placed opposite to each other.

It will be seen that in both constructions the exposed surfaces of thetubes over which the liquid to be heated or cooled flows, collectivelyform a series of horizontal corrugations which are entirely free fromangles so that such surface can be readily cleaned, and further, suchsurface is practically wholly formed by the metal of the tubes.

What I claim then isz- In a body for heat exchange apparatus, thecombination of a vertical partition plate, tubes secured to oppositesides of said plate, said tubes having each a at base secured to thepartition plate, beaded edges of substantially part circular formadjacent the base, and converging sides, said tubes being disposedadjacent one another with opposed beaded edges almost in contact toprovide an exposed substantially continuous and horizontally corrugatedtube surface.

CHARLES ROBINSON.

